20.500.12556/RUL-174354 Proučevanje biomineralizacije gliv za popravljanje betona Study of fungal biomineralisation for concrete repair Beton je najpogosteje uporabljen gradbeni material, vendar je njegova trajnost omejena z nastajanjem razpok. Kot obetavna, okolju prijazna rešitev za popravilo se uveljavlja biogeno samoceljenje, ki temelji na mikrobno inducirani biomineralizaciji kalcijevega karbonata (CaCO3). Glive so zaradi svoje poliekstremotolerance, ki vključuje tudi odpornost na alkalne pogoje in sposobnost tvorbe spor in micelija, posebej zanimivi kandidati za tovrstne aplikacije. Namen magistrske naloge je bil ovrednotiti potencial 36 izbranih poliekstremotolerantnih glivnih sevov za uporabo pri popravljanju betona. Preverjali smo njihovo sposobnost preživetja v alkalnih pogojih, značilnih za beton, ter karakterizirali njihovo zmožnost biomineralizacije CaCO3. Za ugotavljanje lastnosti sevov smo uporabili presejalne teste alkalotolerance na gojiščih s cementom (pH 9-13). Biomineralizacijo s pomočjo ureazne aktivnosti smo spodbujali na gojiščih z anorganskim (kalcijev nitrat) in organskim (kalcijev laktat) virom kalcija. Nastale kristale smo analizirali z optično in vrstično elektronsko mikroskopijo (SEM-EDS) ter Ramanovo spektroskopijo. Naši rezultati so pokazali, da je 30 od 36 sevov toleriralo pH 10, 14 sevov od 27 pa je uspešno raslo na gojišču, prelitem čez cement z dodatkom diatomejske zemlje (pH 9-10). Večina testiranih sevov je v biomineralizacijskih gojiščih tvorila minerale kalcijevega karbonata, predvsem kalcit, v nekaterih primerih tudi vaterit. Štirje sevi so tvorili tudi kalcijeve oksalate. SEM analiza je potrdila veliko raznolikost morfologij kristalov med sevi ter pokazala, da površina glivnih hif pri nekaterih sevih služi kot nukleacijsko mesto za kristalizacijo. Pri aplikaciji na cementne prizme so glive rastle v razpokah, vendar do pomembnejšega zapolnjevanja z minerali ni prišlo. Rezultati vseeno nakazujejo, da imajo izbrane glive velik biomineralizacijski potencial, vendar so za njihovo učinkovito uporabo v betonu nujne nadaljnje raziskave. Concrete is the most widely used construction material, yet its durability is limited by crack formation. As a promising and environmentally friendly repair solution, biogenic self-healing based on microbially induced biomineralization of calcium carbonate (CaCO3) has been gaining attention. Polyextremotolerant fungi, due to their resistance to alkaline conditions and ability to form extensive mycelium, represent particularly interesting candidates for such applications. The aim of this thesis was to evaluate the potential of 36 selected polyextremotolerant fungal strains for use in concrete repair. We examined their ability to survive in alkaline conditions characteristic of concrete and characterized their capacity for CaCO3 biomineralization. To assess strain properties, we conducted screening tests of alkalotolerance on cement-based media (pH 9-13). Biomineralization via urease activity was promoted on media containing inorganic (calcium nitrate) and organic (calcium lactate) calcium sources. The resulting crystals were analyzed using optical microscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and Raman spectroscopy. Our results showed that 30 out of 36 strains tolerated pH 10, and 14 out of 27 strains successfully grew on cement-coated medium supplemented with diatomaceous earth (pH 9-10). Most tested strains produced calcium carbonate minerals in biomineralization media, predominantly calcite, and in some cases vaterite. Four strains also formed calcium oxalates. SEM analysis confirmed a high diversity of crystal morphologies among strains and revealed that fungal hyphae in some strains served as nucleation sites for crystallization. When applied to cement prisms, fungi grew within cracks, although significant mineral filling did not occur. Nevertheless, the results indicate that the selected fungi have great biomineralization potential, but further research is needed for their effective use in concrete. biomineralizacija glive popravljanje betona mikroskopija alkalofili biomineralization fungi concrete repair microscopy alkalophiles true false false [T. Gabrovšek] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2025-10-01 11:38:28 2025-10-01 11:38:36 2026-10-02 10:16:39 0000-00-00 00:00:00 2025 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 2027-08-26 579.22/.26:582.28:691.32 267242 251860995 54277.pdf 54277.pdf 1 CC05E0DF4A2C1932B45207AFD4346AB3 8bc9f7a305794d5f9974ee570dba3b5223b280ccf8204d30fe58e47ef4a23b29 339176a4-9eaa-11f0-9328-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=219149 Biotehniška fakulteta 0 0 0